python3绘图示例3（基于matplotlib：折线图等）

#!/usr/bin/env python
# -*- coding:utf-8 -*-
from pylab import *
from numpy import *
import numpy

# 数据点图-数据点平滑处理
def moveing_average(ineterval,window_size):
    window=ones(int(window_size))/float(window_size)
    return convolve(ineterval,window,'same')

t=linspace(-4,4,100)
y=sign(t)+randn(len(t))*0.1
plot(t,y,'k.')

y_av=moveing_average(y,10)
plot(t,y_av,'r')

xlabel('time')
ylabel('value')
grid(True)
show()

# 图2-一个为曲线图 一个为折线图
windows=['flat','hanning','hamming','bartlett','blackman']

def smooth(x,window_len=11,window='hanning'):
    if x.ndim!=1:
        print('ere')

    if x.size<window_len:
        print('ee2')

    if window_len<3:
        return x

    if not window  in windows:
        print('4')

    s=numpy.r_[x[window_len-1:0:-1],x,x[-1:-window_len:-1]]

    if window=='flat':
        w=numpy.ones(window_len,'d')
    else:
        w=eval('numpy.'+window+'(window_len)')
        y=numpy.convolve(w/w.sum(),s,mode='valid')
    return y

t=linspace(-4,4,100)
x=sign(t)
xn=x+randn(len(t))*0.1

y=smooth(x)

ws=31
subplot(211)
plot(ones(ws))

for w in windows[1:]:
    eval('plot('+w+'(ws))')
    axis([0,30,0,1.1])
    legend(windows)
    title('smoothing')

subplot(212)
plot(x)
plot(xn)
for w in windows[1:]:
    plot(smooth(xn,10,w))
I=['original ','noise']
I.extend(windows)
legend(I)

title('signal')
show()